The present invention relates to a transmission rod for accessories for windows and doors.
Accessories for windows and doors are divided in two large categories, according to the material constituting the window or door: accessories for wooden or PVC windows and doors and accessories for aluminium windows or doors. The main difference is due to the fact that aluminium windows and doors have grooves with considerably greater structural capacities than those of the grooves of wood or PVC windows and doors. Consequently, whilst accessories for wood and PVC windows and doors must be provided with a support and guide structure with a structural function, accessories for aluminium windows and doors exploit the structural capacity of the guides of the window or door.
In the field of accessories for aluminium windows and doors, transmission rods are used which connect the various accessories of the window or door to each other. In particular, in the case of windows that can rotate both about a vertical axis and about a horizontal axis, transmission rods are provided for connecting the opening/closing device to an upper angular transmission and to a lower angular transmission. Also provided is a transmission rod for connecting the upper angular transmission to a scissors arm and a transmission rod connected to the lower angular transmission. An additional rod, connected to an angular transmission for supplementary closure, can also be provided.
Each transmission rod is provided at it ends with connecting means. For example, such connecting means can be formed by holes able to engage pivot pins provided on the accessories.
The length of the transmission rods depends on the dimensions of the window or door and on the position of the opening and closing device. In more traditional solutions, transmission rods are obtained starting from a continuous strip of metallic or plastic material wherefrom are cut segments with the desired length. After the cut, in each transmission rod are formed connecting holes at the two ends by punching or drilling. The cut to measure and the punching or drilling of the transmission rods are performed by the manufacturer of the windows or doors. Said operations are time consuming for the manufacturer and require dedicated machines.
The document EP-A-1 227 207 describes accessories for windows comprising a support piece connected at its ends to a pair of transmission rods. The support piece is connected to each transmission rod by means of mutually engaged toothed parts, i.e. a toothed part at the end of the transmission rod and a toothed part at the end of the support piece. The toothed coupling between the support piece and the transmission rod, however, allows a relatively reduced amplitude adjustment, so the window and door manufacturer must have available an assortment of rods with different lengths to cover all production requirements.